1. Field of the Invention
The present invention relates to a feed device for installation in a fuel tank having a baffle for collecting fuel, a feed unit for feeding fuel out of the baffle, and a filling-level sensor having a lever arm carrying a float pivotally arranged in a mounting or a carrier arranged on the baffle.
2. Description of the Related Art
Feed devices having baffles in which feed units and filling level sensors are arranged are often used in fuel tanks of present-day motor vehicles. The feed units are supported on the bottom of the fuel tank and are designed as a structural unit together with the baffle. The baffle has a guide with a plurality of orifices arranged at different heights. A carrier is arranged in the guide and has a lug for interlocking with one of the orifices. Accordingly, the carrier is connectable to the baffle at different heights thereby allowing standardized components of the feed device to be used in differently constructed fuel tanks which require different pivoting ranges of the float. The pivoting ranges of the float depend on the height of the fuel tank and on the intended installation position of the baffle or feed unit in the fuel tank.
The baffle is of double-walled design in the region of the guide and the orifices are arranged transversely to the longest extent of the guide. The baffle is consequently highly cost-intensive to manufacture. Furthermore, the baffle requires a high and therefore cost-intensive use of material, since the guide has to extend on the baffle over a region far exceeding the length of the carrier.
An object of the present invention is to provide a feed unit for installation in a fuel tank of a motor vehicle that it is suitable for use in a number of fuel tanks of various configurations and can be produced particularly cost-effectively.
The object is met, according to the present invention, by a feed unit with a filling level sensor having a lever arm including a lever wire holding a float, the level arm being mounted in a carrier that is mountable in different orientations at a predetermined position on a baffle or another device location in the fuel tank.
As a result of this design, the orientation of the lever arm mounted on the carrier and the position of the float may be varied by an appropriate orientation of the carrier. The feed device according to the invention is therefore suitable for use in many different fuel tanks having a variety of configurations. The present invention obviates that need for very long and therefore cost-intensive guides. The feed device according to the invention can therefore be manufactured particularly cost-effectively. Moreover, the feed device according to the present invention requires only a very small amount of construction space because the carrier may be fastened on the feed unit or on the baffle at a position that is determined irrespective of the fuel tank design.
According to another embodiment of the present invention, when the filling level sensor comprises a potentiometer for measuring a position of the lever arm, corrosion of a resistance slide track arranged on the carrier may be avoided by arranging the carrier on the inside of the baffle. This configuration ensures that the resistance slide track is covered with fuel at all times. Moreover, as a result, the filling-level sensor operates with a high degree of accuracy. The position of the lever arm may alternatively be detected via a magnetically passive position sensor, in which a magnetic network arranged on the carrier detects the position of a magnet arranged on the lever arm and coverts it into electrical signals.
According to yet a further embodiment of the present invention, the baffle or the feed unit may be designed particularly cost-effectively as cylindrical components when the carrier has vertical strips arranged for connecting the carrier to the baffle or to the feed unit.
The feed device according to the present invention is of particularly simple design when the carrier has a first carrier part connected to one of the baffle and the feed unit and a second carrier part on which the lever arm is mounted. The carrier parts are positively connected to one another and may also be constructed in a particularly simple way.
The first carrier part may be connectable to the baffle or feed unit in different orientations. However, a further simplification of the construction of the feed unit according to the invention is made when the second carrier part is mountable in at least two different orientations on the first carrier part. In a simple example, the second carrier part may be fastened at different offset angles.
The feed device according to the invention is of particularly simple design when a position sensor converting the position of the lever arm into electrical signals is arranged on the second carrier part.
The mounting of the feed device according to the present invention is particularly simple when the carrier parts are connected to one another via a latching connection.
A further simplification of the manufacture of the components of the feed device according to the present invention is made when the second carrier part has lugs facing the first carrier part and when latching means of the first carrier part are provided for engaging behind the lugs and prestressing the second carrier part against a stop. As a result, the carrier parts can in each case be manufactured cost-effectively in an axial-removal injection mold. Undercuts requiring the use of cores in the injection mold are avoided by this design.
The feed device according to the present invention may be mounted in a particularly large number of differently configured fuel tanks if a lever wire of the lever arm holding the float is connectable to the yoke of the lever arm in different orientations to set an intended pivoting range of the float. In conjunction with the carrier design according to the present invention, this design of the lever arm makes it possible to multiply the possibilities for setting the pivoting range of the float.
According to another embodiment of the present invention, the yoke is guided with particular accuracy when the carrier possesses tracks which are arranged on mutually opposing regions of the mounting and on which the yoke is supported or guided. Accordingly, as the yoke pivots about the mounting, the radial outer regions of the yoke are guided in the tracks arranged on opposing sides of the mounting. This contributes to increasing the accuracy of the signals from the position sensor.
A further simplification of the mounting of the feed device according to the invention is made if latching connections provided for holding the lever wire on the yoke are arranged on a plurality of legs of the yoke which point away from the region of the mounting.
According to another embodiment of the invention, the pivoting range of the lever arm may be limited at particularly low outlay if the carrier has two stops for limiting the pivoting range of the yoke.
The pivoting range of the float in the fuel tank will be changed in a simple way by different fastenings of the lever wire to the lever if the carrier has stops for limiting the pivoting range of the lever wire.
If the carrier is fastened in the baffle, the top edges of the baffle may be used as a stop of the pivoting range of the lever wire.